The present invention relates to a mechanism for locking a container for valuables such as a safe or money box of the type having two doors or access openings, one for loading items such as currency and the other for unloading the items when the safe is full.
Mobile safes having upper loading doors and lower unloading doors are commonly used in vaults for depositing the contents of fare boxes or coinboxes used, for example, in automatic vending machines for transportation tickets or other articles. In one typical case a transportation system will have automatic ticket machines on buses or at transit stops, for example, in which travellers can deposit money to purchase a ticket. The machine will have a removable secure cash or money box for collecting the money. Full cash boxes must be removed and replaced periodically by an operator. They may contain coins and note currency. The full cash boxes are normally taken to a vault where the money they contain is transferred into a secure safe within the vault. When the safe is full it must itself be removed from the vault for emptying via its unloading doors in a secure counting room.
The mobile safe must therefore be securely locked when removed from the vault so that neither the loading or unloading doors can be opened without the necessary master key. The locking mechanism must be relatively tamper-proof to reduce the risk of theft. At the same time the upper loading door of the safe must be releasable when the safe is within the vault or outer housing so that money can be deposited in the housing.
Thus in the past various locking mechanisms have been devised for mobile safes and coinboxes which automatically lock the loading door when the safe is released from the outer housing, and allow the loading door to be opened only when the safe or coinbox is empty and locked in the outer housing or vault.
In U.S. Pat. No. 3,016,185 of Osborne a coinbox is described which has an upper chute for depositing money in the coinbox when it is locked in the outer housing. In order to remove the coinbox an operator must turn a key to release latch arms on the coinbox from openings in the housing. Rotation of the key also acts to slide a plate into place to obstruct the chute. Thus the coinbox can only be removed when the chute is blocked. The operator is prevented from turning the key back to release the chute when the coinbox has been removed from the housing by a ratchet and pawl mechanism which is engaged by unlocking rotation of the key. This mechanism must be released once the coinbox has been emptied at a central location to allow the chute to be re-opened when the empty box is replaced in a housing, and this is done with a master key.
A similar type of coinbox locking device is described in the U.S. Pat. No. 3,083,896 of Cairelli et al in which a coinbox is locked in a container by means of a bolt. The bolt is actuated by a two key operated lock assembly. The bolt actuates a blocking lever to prevent access to the coin slot when the box is released from the container.
In U.S. Pat. No. 3,108,741 of Thomas a mechanism is described in which cash openings in a cash vault are opened by engagement of a stud on the vault with a coin plate mounted on the underside of the coin machine and locked closed by removal of the vault from the machine.